136 PROCEEDINGS OF THE ACADEMY OF [PaRT I 



This C/in/samoe6a -Flagellate (Plate VII, fig. 43), 18 to 20[x in 

 length, is ovate, with the broader extremity either anterior or poste- 

 rior according to the individuals , sometimes it is somewhat stretched 

 behind. It contains a distinct, curved chromatophore, a small con- 

 tractile vesicle near the anterior extremity, very small shining gran- 

 ules, and often a large spherule of pure leucosine; the nucleus gen- 

 erally remains indistinct, hidden in the curve of the golden-green 

 chromatophore; the flagellum, very thin, hardly longer than the 

 body, takes its origin from a very small notch, above which the 

 anterior extremity rises in a small prominence. 



After swimming about for a time whose duration I could not 

 make sure of,^^ the Flagellate again comes to the amoeba stage, and 

 contracts into a spherule (Plate VII, fig. 42), the surface of which 

 soon begins showing small projecting denticulations, then each of 

 these protuberances develops into a very thin pseudopod, which 

 soon thickens, at the same time the flagellum gets more indistinct, 

 it is thin, flabby, and remains for a long time at rest; now and then, 

 however, it seems to come to life again, and oscillates for a brief 

 moment; and finally it disappears, either collapsed, or rather — if 

 a single observation entitles to ajudgment — resolves into a chaplet 

 of tiny pearls, which are lost by and by. 



Division has rarely been observed. As far as I know, Klebs and 

 Scherffel alone have mentioned a few cases, and one cannot but be 

 somewhat surprised at the rarity of the occurrence, when thinking 

 of these big colonies whose constituent members might be sup- 

 posed to arise from a single primary individual. As it is, I was 

 able to verify a few cases of division, but only one of these could 

 be studied at length. The animalcule was found already somewhat 

 stretched in length (Plate VII, fig. 44, a), and was provided with 

 two chromatophores, still united, which together had the shape 

 of a W; to the left, a big mass of leucosine ; to the right, a very large 

 vacuole. Two minutes after that first observation, the chroma- 

 tophores were separated, the vacuole had grown bigger still, and 

 the leucosine globule had elongated (Plate VII, fig. 44, h); a Httle 

 later, the 8 -form of the body was much more apparent (Plate VII, 

 fig. 44, c), the leucosine body was still more elongated; the big vacu- 



" The resting or amoeba state, whose duration is not difficult to notice, can 

 last for days, but this duration may also be much reduced, and 1 have seen for 

 instance a flagellated individual transform into an amoeba and develop pseu- 

 dopods; but two hours later the little organism had disappeared again as if 

 not satisfied with the new condition. 



